Preventing influenza coinfection among HIV-infected persons: a complex picture coming into focus

[Vaccination against pneumococci and influenza. How good is the evidence?]

Diseases caused by pneumococci and influenza viruses can lead to severe complications in children, in older, chronically ill and immunosuppressed patients. In an aging population in western countries they present an important cause of morbidity and mortality. Additionally, antibiotic resistance may complicate a therapy. Consequently, the need of an effective vaccine is obvious. The 23-valent polysaccharide pneumococcal vaccine has been discussed critically. New meta-analyses do not show an efficacy in preventing invasive pneumococcal disease or death of all cause. However, a very recent study has shown a significant reduction of pneumonias and death due to pneumococcal disease in nursing-home residents. The 7-valent conjugated vaccine is more immunogenic and efficient in children and first studies demonstrate its efficacy in immunosuppressed persons. In Switzerland this latter vaccine is used in children, in Germany the 7-valent vaccine has been replaced by the 13-valent conjugated vaccine since December 2009. Influenza-vaccines are effective, while vaccines with an adjuvance seem more immunogenic, in particular in older persons. The 2010/2011 influenza vaccine has been adapted and includes the pandemic influenza H1N1 2009 strain. The influenza vaccine often does not provide protection against infection, however, it does provide good efficacy against severe complications related to influenza.